wordpress blank image

Try Reviewing:
https://mhthemes.com/support/knb/fix-blank-thumbnails-wordpress-media-library/#:~:text=Refresh%20the%20media%20library%20to%20see%20if%20your,thumbnails%20can%20fix%20thumbnail%20issues%20caused%20by%20themes.

https://www.wpbeginner.com/wp-tutorials/how-to-fix-image-upload-issue-in-wordpress/

I have tried all these solutions but didn’t work

This may be a plugin or theme conflict. Please attempt to disable all plugins, and use one of the default (Twenty*) themes. If the problem goes away, enable them one by one to identify the source of your troubles.

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If you can install plugins, install and activate “Health Check”: https://www.ads-software.com/plugins/health-check/
It will add some additional features under the menu item under Tools > Site Health.
On its troubleshooting tab, you can Enable Troubleshooting Mode. This will disable all plugins, switch to a standard WordPress theme (if available), allow you to turn your plugins on and off and switch between themes, without affecting normal visitors to your site. This allows you to test for various compatibility issues.
There’s a more detailed description about how to use the Health Check plugin and its Troubleshooting Mode at https://make.www.ads-software.com/support/handbook/appendix/troubleshooting-using-the-health-check/

I tried with this “Site health”, the plugin disable all the themes and plugins, then I try to upload new image, it still showing me same blank thumbnail.

Try checking with your hosting provider if they have some restrictions.